Onavo, which began as an Israeli analytics startup focused on helping users monitor their data usage, was acquired by Facebook in 2013. Its VPN provider then became a data collection tool for Facebook to monitor smartphone users’ behavior outside its core apps, helping inform Facebook’s live video strategy, competition from other social apps, and its decision to acquire companies including WhatsApp.

Onavo Protect is a VPN service Facebook used to monitor users’ smartphone behavior

“We’ve always been clear when people download Onavo about the information that is collected and how it is used,” said a Facebook spokesperson in a statement given to The Verge. “As a developer on Apple’s platform, we follow the rules they’ve put in place.”

Apple did not forcibly pull the app, but it does seem to have pressured Facebook into removing it. According to the Journal, Apple informed Facebook earlier this month that Onavo Protect violated new privacy rules, implemented back in June, that restrict developers’ ability to create databases out of user information and sell it to third parties.

Onavo Protect also allegedly violated a part of the iOS developer agreement that regulates how app makers make use of data outside the core function of the software. Onavo Protect is a VPN service, and yet Facebook has been using the traffic routed through its private servers for broad analytic purposes. Apple was not immediately available for comment

According to the report, discussions between Apple and Facebook occured last week, and Apple suggested that Onavo Protect be voluntarily removed from the App Store. Facebook agreed, and the app is scheduled to be pulled later today. Users who have already downloaded Onavo Protect can continue using it on iOS devices, but Facebook will be unable to issue updates. The Android version of the app will remain in Google’s Play Store, WSJ notes.